Electricity
The common power supplied to most wired devices, where the current reverses its direction many times per second. This type of power is generated and distributed throughout settled areas.
Alternating current (AC)
A bit designed for use in wood or similar soft material. The design allows it to drill a flat-bottom blind hole in the material.
Forstner bit
A small lever, switch, or part that activates a locking catch or spring to hold a power tool trigger in the operating mode without finger pressure.
Trigger lock
The channel created by a saw blade passing through the material, which is equal to the width of the blade teeth.
Kerf
A small, T-shaped steel piece used to open and close the chuck on power drills. Cordless drills typically do not have a chuck key.
Chuck key
An electric power supply in which the current flows in one direction only. This power is supplied by batteries and by transformer-rectifiers that change the power delivered.
Direct current (DC)
A drill bit that uses a lead screw to pull the larger rear portion of the bit into the wood, making it simple to drill larger holes.
Self-feed bit
A safety attachment used to prevent whiplashing in hoses when they are inadvertently uncoupled.
Whip check
A substance, such as sandpaper, that is used to wear away material.
Abrasive
The smooth part of a drill bit that fits into the chuck.
Shank
A measurement of the power the tool can deliver.
Voltage rating
A drill bit with a carbide tip designed to penetrate materials such as stone, brick, or concrete.
Masonry bit
Protection against short circuits; a safety device cuts off power as soon as it senses any imbalance between incoming and outgoing current.
Ground fault protection
OUT OF PLACE: Moving backward and forward on a straight line.
Reciprocating
A clamping device that holds an attachment; for example, the chuck of the drill holds the drill bit.
Chuck
Describe one complete charge and discharge cycle for a rechargeable battery.
Charge cycles
A drill bit that includes steps that enable the user to cut holes in metal to a desired diameter.
Step drill bit
A circuit breaker that is designed to protect people from electric shock and to protect equipment from damage by interrupting the flow of electricity if a circuit fault occurs.
Ground fault circuit interrupter (GFCI)
A granular, sand-like material used to make sandpaper and similar materials abrasive.
Grit
A bit or drill used to set the head of a screw at or below the surface of the material.
Countersink
A rating that describes the maximum amps a battery can provide continuously for up to 60 minutes. You can draw more amps than the battery’s rating, but it reduces how long the battery lasts.
Amp hour (Ah)
A drill bit with a spiral cutting edge for boring holes in wood and other materials.
Auger bit
OUT OF PLACE: The rotational speed of a motor or shaft, based on the number of times it rotates each minute.
Revolutions per minute (rpm)
A very hard material made of tungsten and heavy metals such as cobalt. Commonly baked onto the tips of masonry bits and the edges of saw blades.
Carbide
The end of a circular saw shaft where the blade is mounted.
Arbor